نشریه یافته های نوین در علوم زیستی
سال دوم شماره 3 (پیاپی 5، پاییز 1394)

Pimpinella anisum L. belongs to Apiaceae family. The samples of vegetative and reproductive organs at different stages of development were gathered and investigated by cell-histology methods. The investigation of the anatomical structure of vegetative organs showed that the secretory ducts are arranged between the parenchymal tissues of the leaf. Section of flower buds revealed that anthers had 4 pollen sacs, the division of pollen mother cell was of the simultaneous type, microspore tetrads were of tetragonal type and the tapetum layer was secretory. The study of the ultrastructure of pollen grains with SEM showed that they had 3 pores. The ovary was found to be two-chambered and two-carpeled the ovule to be anatropous and to have one membrane. In embryogenic investigation it was found that the embryos were globular, cotyledonary and torpedo-shaped and the transition between globular embryos to cordate embryos was found. The vegetative organs were observed to have the general structure of dicotyledons. The development patterns of ovule and embryo sac follow the Polygonum type. Tetrahedral microspore tetrads were observed. The ultrastructure of pollens was found to be similar to those of Smyrnium, a genus of Apiaceae family. All stages of embryogenesis were covered in this study.

The aim of this study was to investigate the possibility of using rice bran as a natural adsorbent for the removal of citric acid from water and the effect of temperature, time, initial concentration of adsorbate and adsorbent concentration on the adsorption process. Fitting experimental data was performed using several adsorption models. Also, the thermodynamics and kinetics of adsorption have been studied. The equilibrium was reached after 60 minutes. The results showed that removal of citric acid decreased as temperature and initial concentration of citric acid increased in contrast, it increased as adsorbent concentration and time increased. In addition, the optimum adsorbent weight was obtained to be 4g. Freundlich isotherm was found to be a better fit than other isotherms. The thermodynamic study showed that the adsorption process was exothermic and spontaneous in nature. The adsorption of citric acid on the rice bran followed reversible second-order rate kinetics. This study showed that rice bran efficiently removed the citric acid from aqueous solutions.

Boujagh National Park, with water ecosystems including Boujagh and Kiashahr wetlands, has an area of approximately 3477.3 hectares. In order to study factors affecting the vegetation in aquatic and wet habitats, 44 releves were implemented in the region. To test the chemical properties of the available water, samples were collected from 22 releves. The results of a two-way species indicator analysis of the modified TWINSPAN suggested that four groups of plants were present in the region. The first group being floating, immersed and submerged and the third and fourth groups being mostly helophytic. The second group of plants grows in areas with sand and mud. The results of comparative DCA analysis of water factors (PH, Depth, P, N, Cl, CO3, Hco3, EC, Na, K) showed a significant correlation between the factors and plant groups and the most important factors influencing the distribution and separation of plants was found to be water depth. In addition, Boujagh and Kiashahr wetlands vegetation map, based on the plant groups, was also prepared.

This investigation was carried out to evaluate Indole acetic acid (IAA) production by isolated bacteria from drought and salinity affected soils. Four hundred bacteria were isolated from soils with different levels of electrical conductivity (EC) and sodium adsorption ratio (SAR). Then the ability of these bacteria to produce IAA and the effects of different amounts of tryptophan and drought-salinity tensions on IAA production were analyzed. Results indicated that the effects of drought and salinity tensions on variability of IAA production were statistically significant. One of the bacterial species isolated from saline-sodic soils, Arthrobacter siccitolerans, was IAA producer and data comparison indicated that under drought stress conditions it produced IAA 84.3% higher than isolate RS11. While isolated RS11 produced highest rate of IAA (10.42 µg.ml-1) under normal conditions. Also, A.siccitolerans continued to produce IAA until the EC was 40 dS.m-1 and OP (Osmosis pressure) was -20 bar. The amount of IAA production per unit of applied tryptophan in this bacterium was 0.1 and in others it was lesser. According to experiments, the relative preference of this bacterium was verified and proposed for field experiments in drought, salinity and salinity-sodicity affected soils.

There is no report on the antimicrobial effects of evening primrose (Oenothera biennis L.) and borage (Echium amoenum Fisch. & C.A.Mey.). In this research, the seeds of these plants were milled and extracted by chloroform:methanol (2:1). Then, the solvents were evaporated under reduced pressure and temperature to extract the oils. Antimicrobial effects of various concentrations of the oils (10- 1000 mg/l) were assessed against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger. Minimum inhibition concentration of the oils for each strain was measured using Mueller Hinton Broth and Sabouraud Dextrose Broth. The results showed that evening primrose oil increased the growth of C. albicans and A. niger, while it suppressed the growth of S. aureus, S. epidermidis and P. aeruginosa even at the minimum concentration level (1mg/l). Borage oil was found to promote the growth of A. niger and S. epidermidis, but at concentration levels equal to or higher than 1mg/l it inhibited the growth of P. aeruginosa and C. albicans. However, at no concentration level, was it observed to leave any effect on S. aureus. It was also shown that some medical properties of evening primrose and borage could be attributed to antimicrobial effects of their oils.

Danio rerio Hamilton, 1822 is one of the commercial ornamental fresh water fishes and living in tropical zones, of considerable economic value in our country. This study aimed at investigating the impact of Spirulina sp. on index color in Danio rerio. 360 individuals were randomly divided in 12 aquariums with 4 treatments and 3 replications. The dietary treatments included treatment 1 or control (commercial food with no supplement of Spirulina sp.), treatment 2 (commercial food with 0.5% supplement of Spirulina sp.), treatment 3 (commercial food with 1% supplement of Spirulina sp.) and treatment 4 (commercial food with 1.5% supplement of Spirulina sp.). In general, the use of Spirulina sp. in the diet of Danio rerio caused increase in body weight and specific growth rate, but increasing the amount of dietary of Spirulina sp. powder in the diet of Danio rerio during the breeding period of 60 days had no impact on the feed conversion ratio. There being no significant difference between treatments 1% and 1.5 %, treatment 1% of supplement Spirulina sp. was found to be the best treatment for growth in Danio rerio.

Electromagnetic field is a stress factor which can interfere with the functions of body organs. This study aims to evaluate the protective impact of the aqua extract of Persian Gulf sea cucumber on damages induced by low frequency electromagnetic field in male gonads of Balb/C mice. Mice were divided into control, sham-exposed and 5 experimental groups. The experimental groups were then exposed to electromagnetic field (for 10 days and 4 hours per day). Experimental groups 2-5 also received extract of sea cucumber (6h before electromagnetic field). The samples were fixed for histological studies and stained by H & E method. The measurement of the diameter and number of seminiferous tubules, testis diameter, testis and epididymis weight, tunica albuginea thickness, the number of spermatogenic cells including spermatogonia, spermatocytes, spermatids, Sertoli cells and Leydig cells was then executed. The results showed that the impact of electromagnetic field exposure was not significant on epididymis weight, seminiferous tubules diameter and tunica albuginea thickness, while its impact on the reduction of the testis diameter and weight, the number of seminiferous tubules and spermatogenic cells was significant in experimental group 1. In addition, the experimental groups pre-treated with sea cucumber extract indicated significant increment, as compared with experimental group 1.The results proved the destructive effect of electromagnetic field on testis tissue parameters, while sea cucumber extract prevents damages induced by electromagnetic field on male sexual glands of mice.

Breast cancer is the most common cancer worldwide and is the second leading cause of death in women after lung cancer. Micro RNAs (miRNAs) are among endogenous factors which are involved in many types of cancers, including breast cancer. Single nucleotide polymorphism (SNP) in the miRNAs, might change their biological activities such as their effects on oncogenes and tumor suppressor genes. Therefore some of miRNA’s SNPs are associated with the risk of different types of cancer, including breast cancer. The aim of this study was to evaluate the correlation between SNP rs11614913 in mir196a2 and the risk of breast cancer. SNP rs11614913 in hsa-miR-196a2 analyzed in 100 breast cancer cases and 100 controls in women living in southern Iran. Polymorphism was identified by the PCR-RFLP method. The PCR product was digested with TaaI restriction enzyme which produced two bands with the length of 187bp and 196bp. The data from this case –control study were analyzed using odds ratios (ORs) with 95% confidence intervals (CIs) to reveal the associations of SNPs in miRNAs with breast cancer susceptibility. The C allele frequencies in patients and controls for miR-196a2 were 0.74 and 0.75, respectively. The genotype frequencies of TT, TC, and CC were 0.05, 0.42, and 0.53 for the patients and 0.06, 0.38, and 0.56 for the controls, respectively. Statistical analysis showed that the genetic frequencies for this SNP were in Hardy-Weinberg equilibrium (p>0.05). The results of this study indicated no significant association between SNP rs11614913 in mir196a2 and the risk of breast cancer.